The Black Ha Nhi live on a rocky mountain which rises 2,000m above sea level and is almost always shrouded in clouds. They live in earthen houses with very thick walls to protect them from the cold.

They carefully collect wood and choose an auspicious day to start a new house. 

Doctor Tran Huu Son, Vice Chairman of Vietnam’s Folklore Arts Association, said, “They have taboos about collecting wood to build a house. They must cut the trees in the dry season, not the rainy season. On their way to the forest, if they encounter a snake or anything odd, they go no further and return home. Only the head of the family clan or another prestigious man is allowed to cut the trees.”

Building a house is a major event in a man’s life. Ly Mo Xa of Kin Chu Phin 2 hamlet shared his experience in selecting trees. He said, “We choose an auspicious day to cut the trees, which is often the 2nd or 3rd day of the 2nd month. The trees must not be damaged by lightning or affected by termites. If we use such trees to build a house, we’ll experience bad luck in the future.”

The Black Ha Nhi believe that happiness and prosperity depend largely on the proper placement of the house. It should be close to a water source, near the foot of the mountain, its back to the mountain, and facing a large field. The house should not overlook graves.

All Ha Nhi men can build earthen houses. The construction begins in the dry season, from the 8th to the 12th lunar month. Ly Di Go of Kim Chu Phin 1 hamlet said his house was built 10 years ago. It looks like a brown bunker in the forest.

“The earthen walls are about 40cm thick. It’s a mixture of clay and rock. We have to dig deep to get the best clay to build the walls,” he said.

The men use wood planks to form wall frames, fill them with a mixture of clay and rock, and ram it down. When the lower part is dry and solid, they raise the wood frames higher to make a wall 4 or 5 meters high. 

Ly Mo Xa added, “Ramming soil takes skill. We have to use all our strength to make it firm otherwise the walls will collapse.”

The roof has 4 sides made of alang grass. Several layers of alang grass will make the house warm and durable.

A house of the Black Ha Nhi in Lao Cai has high walls, sloping roofs, no porch, and just one door. Its thick walls keep the family warm and protects them from outside dangers. 

Doctor Tran Huu Son said, “Loopholes in the walls turn the house into a fortress. The thick earthen walls are for defense, protection against the wet mountain weather, and keeping the house warm in winter and cool in summer.”

In hundreds of years of living in the high mountains, the Ha Nhi have perfected their mushroom houses, which now are becoming a fascinating attraction for tourists.